Help Battery Problems

[androidfear93]

I charged my 7015 for a few hours today, but when I unplugged it, it said it was low on battery. So I plugged it back in and it started charging but the number shot up sporadically, and when I unplugged it again it went back down to 13%. Please help I dont know what to do about battery problems like this.

 

[androidfear93]

I dont really use it anymore so maybe help isn't necessary. But im still open to any help cause then I can sell it.